Have you ever noticed that a lot the times when you see a train being pulled by multiple locomotives that whether there are two or five locomotive units or more, the ones on the ends are always pointing away from each other and the ones in between may be pointed in either direction? Since diesel-electric locomotives can travel either direction just as easy, why would they go to all the trouble of turning one around so that the ones on both ends are pointed in opposite directions? Well, that is the answer. It is a lot of trouble to turn one around, so the least amount of times it needs to be done the more time (and thus cost) will be saved. The locomotive units stay together as a whole and from then on can head up a train going in either direction.
Have you ever heard the expression, "I wouldn't touch that with a ten foot pole"? Why a ten foot pole, wouldn't an eight foot or a twelve foot pole do? It so happens that this explanation also is connected to the transportation industry, only this time not on rail but on the water. Riverboats back in the day were propelled by a person using a ten foot pole. Ten feet was about right for pushing off the banks, rocks, and obstructions and also for pushing over sand bars, etc. Also, because all the poles were ten feet long, they were also used as measuring sticks and depth gauges. I am sure they could be used for other things but I wouldn't touch that with a ten foot pole. So, don't drop your pole or get it stuck in the mud and have a wonderful day, you hear?